If you want a reliability upgrade. I used the head off an 06 Raptor 350 when I rebuilt my 2000 a while back. there are extra oiling ports on the rockers arms.
You should be able to look at early model Raptor 350 motors for parts as well. pretty sure they were the same as your 2002. Mines a 2000 and I put a new 2006 Raptor cylinder head on it. I haven't really kept up with them lately so not really sure how many years into the Raptor line up you can...
I've got the White Brothers E2 and love it. easy to tune, and you can make it loud or fairly quiet if you want to. Also running the FMF PowerBomb header the two make a great combination.
Just saw Antietam Motorsports Park is re-opening in Hagerstown, MD in the spring of 2013. I moved here just in time for it to close, so never been there. It's got 5 miles of woods trails and a MX track from the sound of it.